How to select an int datatype field(bonus) which is inserted as NULL?
如何选择插入为NULL的int数据类型字段(奖金)?
Tried the following but prints nothing though there is a valid entry.
试过以下但是虽然有一个有效的条目但没有打印。
select e_name from employee, payroll where datepart(year,hire_date)=2005 and employee.e#=payroll.e# and bonus=null
also if i want to add another year say 2007 to be checked with 2005 using or, what is the query for that?
另外如果我想添加另一年说2007年要用2005检查,或者是什么查询?
1 个解决方案
#1
3
When testing for null, you must use this syntax:
测试null时,必须使用以下语法:
...
and bonus is null
FYI the syntax for testing if not null is bonus is not null.
FYI测试语法如果不为null则奖励不为空。
All other comparisons (eg =, <, like, etc) will return false with a null value.
所有其他比较(例如=,<,like等)将返回false并返回null值。
#1
3
When testing for null, you must use this syntax:
测试null时,必须使用以下语法:
...
and bonus is null
FYI the syntax for testing if not null is bonus is not null.
FYI测试语法如果不为null则奖励不为空。
All other comparisons (eg =, <, like, etc) will return false with a null value.
所有其他比较(例如=,<,like等)将返回false并返回null值。